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A structural study and its relation to dynamic heterogeneity in a polymer glass former
Cristian Balbuena1, Melisa Mariel Gianetti, Ezequiel Rodolfo Soulé
1Institute of Materials Science and Technology (INTEMA), University of Mar del Plata and National Research Council (CONICET), J. B. Justo 4302, 7600 Mar del Plata, Argentina. cbalbuena@fi.mdp.edu.ar ersoule@fi.mdp.edu.ar.
Soft Matter
|March 4, 2021
Summary
This study links polymer glass structure to dynamics, finding that structural changes below a critical temperature influence relaxation behavior and suggesting a thermodynamic basis for the glass transition.
Area of Science:
- Condensed matter physics
- Materials science
- Polymer physics
Background:
- The relationship between structure and dynamics in glassy materials, specifically super-Arrhenius relaxation and heterogeneous dynamics, is a key unresolved issue.
- The thermodynamic origin of these dynamic phenomena in glass formers remains unclear.
Purpose of the Study:
- To investigate the interplay between structural and dynamic properties in a polymer glass-former.
- To determine if structural conditioning influences the observed dynamic behaviors, such as non-Arrhenius temperature dependence.
Main Methods:
- Utilized molecular dynamics simulations to analyze dynamic and structural parameters.
- Examined short-range order parameters and their correlation with single-particle dynamics.
Main Results:
- Confirmed that structural properties significantly impact dynamic behavior in polymer glass formers.
- Observed that structural conditioning becomes pronounced below the onset of non-Arrhenius behavior and intensifies approaching the glass transition temperature.
- Established a relationship between short-range order and local single-particle dynamics.
Conclusions:
- The findings support a strong connection between structure and dynamics in glassy systems.
- The results suggest that the glass transition may have an underlying thermodynamic origin.
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